An object travels North at 8 m/s for 9 s and then travels South at 5 m/s for 2 s. What are the object's average speed and velocity?

1 Answer
May 11, 2016

v_a=5.64 " "m/s

u_a=7.45" "m/s

Explanation:

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vec AB=8*9=72 " "m
vec CD=5*2=10 " "m

"distance="AB+CD=72+10=82 " "m
"displacement="vec AB-vec CD=72-10=62 " "m

"average velocity"=(displacement)/(time)

v_a=62/(9+2)

v_a=62/11

v_a=5.64 " "m/s

"average speed="(distance)/(time)

u_a=82/11

u_a=7.45" "m/s